I bought a pair of Randall's, with pistol shrimp, from DD a few years back and put them in a 75 gallon tank. The larger Randall proceeded to harass the smaller to death and also harassed 2 dart gobies and 2 other small gobies to death. I don't know if it was a "rogue" Randall's or not, but it wouldn't back down from any fish that came anywhere near it's burrow and seemed very agressive.